Light valve panel and liquid crystal display using the same

ABSTRACT

A light valve panel and a liquid crystal display using the same are discussed. The light valve panel according to an aspect includes a liquid crystal layer, a first electrode including a block corresponding one-to-one with a light valve data line, and a second electrode facing the first electrode with the liquid crystal layer interposed therebetween. An angle between a vertical edge of the block and the light valve data line is greater than 0° and less than 90°. The liquid crystal display device according to another aspect includes a display panel, a backlight unit, and a light valve panel.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Korean PatentApplication No. 10-2016-0067777 filed on May 31, 2016, the entirecontents of which is incorporated herein by reference for all purposesas if fully set forth herein.

BACKGROUND Field of the Disclosure

The present disclosure relates to a liquid crystal display capable ofcontrolling an amount of light incident on a display panel based on aluminance distribution of an input image.

Discussion of the Background

Various flat panel displays, such as a liquid crystal display (LCD), anorganic light emitting diode (OLED) display, a plasma display panel(PDP), and an electrophoretic display (EPD), have been developed. Aliquid crystal display displays an image by controlling an electricfield applied to liquid crystal molecules based on a data voltage. Anactive matrix liquid crystal display includes a thin film transistor(TFT) at each pixel.

A liquid crystal display includes a display panel having a liquidcrystal layer, a backlight unit irradiating light onto the displaypanel, a source driver integrated circuit (IC) for supplying a datavoltage to data lines of the display panel, a gate driver IC forsupplying gate pulses (or scan pulses) to gate lines (or scan lines) ofthe display panel, a control circuit for controlling the source driverIC and the gate driver IC, and a light source driving circuit fordriving light sources of the backlight unit.

Gray levels of an input image are produced by the data voltage appliedto the pixels of the display panel. A liquid crystal display is not goodin displaying a dark image due to the backlight. This is because thebacklight unit irradiates the same amount of light onto the entirescreen of the display panel regardless of luminance distribution of theinput image. Hence, the liquid crystal display has a limited contrastratio.

SUMMARY

In one aspect, there is provided a light valve panel including a liquidcrystal layer, a first electrode arranged in a matrix form and includinga block corresponding one-to-one with a light valve data line, and asecond electrode facing the first electrode with the liquid crystallayer interposed therebetween. An angle between a vertical edge of theblock and the light valve data line is greater than 0° and less than90°.

In another aspect, there is provided a liquid crystal display deviceincluding a display panel on which pixels to which an input image isapplied are arranged, a backlight unit irradiating light onto thedisplay panel, and a light valve panel disposed between the displaypanel and the backlight unit, and which adjusts an amount of light fromthe backlight unit depending on the input image. The light valve panelincludes a liquid crystal layer, a first electrode arranged in a matrixform and including a block corresponding one-to-one with a light valvedata line, and a second electrode facing the first electrode with theliquid crystal layer interposed therebetween. An angle between avertical edge of the block and the light valve data line is greater than0° and less than 90°.

In a further aspect, a light valve panel having first and secondsubstrates configured to adjust an amount of light from a light sourcein accordance with an input image to be displayed, the light valve panelincludes a first electrode on the first substrate and divided by aplurality of blocks, a light valve data line supplying a light valvevoltage to the first electrode, each block corresponding to the lightvalve data line, a second electrode on the second substrate and facingthe first electrode, and liquid crystal molecules between the first andsecond substrates, wherein the liquid crystal molecules are synchronizedwith the input image to be displayed by the light valve voltage.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the disclosure as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this specification, illustrate aspects of the disclosure andtogether with the description serve to explain the principles of thedisclosure.

In the drawings:

FIG. 1 is a block diagram of a liquid crystal display according to anaspect of the disclosure;

FIG. 2 is a cross-sectional view illustrating a stack structure of adisplay panel, a light valve panel, and a backlight unit shown in FIG.1;

FIG. 3 illustrates a moire pattern caused by an inference of lightgenerated when metal lines of a display panel and metal lines of a lightvalve panel overlap each other;

FIG. 4 illustrates a distortion of color generated by a gap between adisplay panel and a light valve panel;

FIG. 5 illustrates an example of a distorted bright line caused when adark block adjacent to a bright block in a light valve panel is turnedon so as to prevent color distortion of a side viewing angle;

FIG. 6 illustrates a pixel data modulation method of a display panel anda block luminance control method of a light valve panel;

FIG. 7 illustrates a luminance of a pixel at a side viewing angle whendata and a luminance of a display panel are controlled through a controlmethod illustrated in (C) of FIG. 6;

FIG. 8 is a cross-sectional view of a light valve panel;

FIGS. 9 and 10 are a view illustrating block division of a light valvepanel according to an aspect of the disclosure;

FIGS. 11 and 12 are a view illustrating block division of a light valvepanel according to a comparative example;

FIG. 13 is a view illustrating block division of a light valve panelaccording to another aspect of the disclosure;

FIG. 14 is a schematic diagram illustrating a method for determining anangle of light valve data line; and

FIGS. 15 to 17 illustrate dummy data lines according to the presentdisclosure.

DETAILED DESCRIPTION

Reference will now be made in example aspects of the disclosure, ofwhich are illustrated in the accompanying drawings. Wherever possible,the same reference numbers will be used throughout the drawings to referto the same or like parts. It will be paid attention that detaileddescription of known arts will be omitted.

Referring to FIGS. 1 and 2, a liquid crystal display according to anaspect of the disclosure includes a display panel PNL1 including a pixelarray, a backlight unit BLU irradiating light onto the display panelPNL1, a light valve panel PNL2 disposed between the display panel PNL1and the backlight unit BLU, a first panel driving circuit 10, 20, and30, a second panel driving circuit 11 and 50, and a backlight drivingcircuit 40.

The display panel PNL1 includes a first upper substrate 100 and a firstlower substrate 110, which are positioned opposite to each other with aliquid crystal layer interposed therebetween.

On the first upper substrate 100, a color filter array including blackmatrixes and color filters is formed.

On the first lower substrate 110, data lines DL, gate lines GL, commonelectrodes 22, pixel electrodes 21 connected to TFTs, storage capacitorsCst connected to the pixel electrodes 21, and the like are formed. TheTFTs are respectively formed in subpixels and are connected to the pixelelectrodes 21. The TFTs may be implemented as one of an amorphoussilicon (a-Si) TFT, a low temperature polysilicon (LTPS) TFT, an oxideTFT, and the like. The TFTs are respectively connected to the pixelelectrodes 21 of the subpixels. The common electrode 22 and the pixelelectrode 21 are separated from each other with an insulating layerinterposed therebetween.

The display panel PNL1 may be implemented as one of liquid crystal modesincluding a twisted nematic (TN) mode, a vertical alignment (VA) mode,an in-plane switching (IPS) mode, a fringe field switching (FFS) mode,etc.

Polarizing films 13 and 14 are respectively attached to the first uppersubstrate 100 and the first lower substrate 110 of the display panelPNL1. Alignment layers for setting a pre-tilt angle of liquid crystalsare respectively formed on the first upper substrate 100 and the firstlower substrate 110 of the display panel PNL1. A spacer for maintaininga cell gap of liquid crystal cells Clc may be formed between the firstupper substrate 100 and the first lower substrate 110 of the displaypanel PNL1.

The light valve panel PNL2 is disposed between the display panel PNL1and the backlight unit BLU. The light valve panel PNL2 drives liquidcrystal molecules based on a difference between the voltages applied toa second upper substrate 200 and a second lower substrate 210 of thelight valve panel PNL2 and adjusts an amount of light to be irradiatedonto the display panel PNL1. The light valve panel PNL2 acts as a liquidcrystal shutter that adjusts an amount of light in synchronization withan input image using electrically controlled liquid crystal molecules.

The liquid crystals of the light valve panel PNL2 may be driven in a TNmode. A luminance of the liquid crystal cell Clc in the TN mode may beadjusted depending on a transmittance-voltage curve (hereinafter,referred to as “T-V curve”) of normally white. In the T-V curve of thenormally white, as the voltage decreases, the transmittance increases.Hence, the luminance of the liquid crystal cell increases. On thecontrary, as the voltage increase, the transmittance decreases. Hence,the luminance of the liquid crystal cell decreases. The structure andoperation of the light valve panel PNL2 will be described later indetail.

The display panel PNL1 and the light valve panel PNL2 may be attached toeach other using an adhesive 23, for example, an optical clear adhesive(OCA).

The first panel driving circuit 10, 20, and 30 applies data of an inputimage to the pixels. The first panel driving circuit includes a firsttiming controller 10, a first data driver 20, and a gate driver 30. Thefirst panel driving circuit 10, 20, and 30 may be integrated into oneIC.

The first timing controller 10 transmits digital video data of an inputimage received from a host system 5 to the first data driver 20. Thefirst timing controller 10 receives timing signals synchronized with thedata of the input image from the host system 5. The timing signalsinclude a vertical sync signal Vsync, a horizontal sync signal Hsync, adata enable signal DE, and a clock CLK, etc. The first timing controller10 controls operation timings of the first data driver 20 and the gatedriver 30 based on the timing signals Vsync, Hsync, DE, and CLK receivedtogether with pixel data of the input image. The first timing controller10 may transmit a polarity control signal for controlling a polarity ofthe pixel array to each of source driver ICs of the first data driver20.

Output channels of the first data driver 20 are connected to the datalines DL of the pixel array. The first data driver 20 receives thedigital video data of the input image from the first timing controller10. The first data driver 20 converts the digital video data of theinput image into positive and negative gamma compensation voltages underthe control of the first timing controller 10 and outputs positive andnegative data voltages. An output voltage of the first data driver 20 issupplied to the data lines DL. The first data driver 20 inverts apolarity of the data voltage to be supplied to the pixels under thecontrol of the first timing controller 10.

The gate driver 30 sequentially supplies gate pulses synchronized withthe data voltage to the gate lines GL under the control of the firsttiming controller 10. The gate pulses output from the gate driver 30 aresynchronized with the data voltage supplied to the data lines DL.

The second panel driving circuit adjusts an amount of light transmittedby the light valve panel PNL2 in synchronization with an input image andimproves a contrast ratio of an image reproduced on the display panelPNL1. The second panel driving circuit includes a second timingcontroller 11 and a second data driver 50. The second timing controller11 and the second data driver 50 may be integrated into one IC.

The second timing controller 11 transmits data of an input image to thesecond data driver 50. The second timing controller 11 receives timingsignals synchronized with the data of the input image from the hostsystem 5. The timing signals include a vertical sync signal Vsync, ahorizontal sync signal Hsync, a data enable signal DE, and a clock CLK,etc. The second timing controller 11 controls operation timing of thesecond data driver 50 based on the timing signals Vsync, Hsync, DE, andCLK received together with pixel data of the input image.

The second data driver 50 receives digital video data of an input imagefrom the second timing controller 11. The second data driver 50 convertsthe digital video data of the input image into positive and negativegamma compensation voltages under the control of the second timingcontroller 11 and outputs positive and negative data voltages. An outputvoltage of the second data driver 50 is supplied to data lines LVL. Thesecond data driver 50 inverts a polarity of the data voltage to besupplied to the pixels under the control of second timing controller 11.

The first and second panel driving circuits may be integrated in varioustypes. For example, the first and second timing controllers 10 and 11may be integrated into one IC. The first and second panel drivingcircuits may be integrated into one IC.

The backlight unit BLU may be implemented as a direct type backlightunit or an edge type backlight unit. The backlight unit BLU includeslight sources LS, a light guide plate LGP, an optical sheet OPT, and thelike. The light source LS may be implemented as a point light sourcesuch as a light emitting diode (LED). Luminances of the light sources LSare individually adjusted depending on a driving voltage supplied by abacklight unit driver 40. The optical sheet OPT includes one or moreprism sheets and one or more diffuser sheets. The optical sheet OPTdiffuses light incident from the light guide plate LGP and refracts atravelling path of light at an angle substantially vertical to a lightincident surface of the display panel PNL1.

The host system 5 may be one of a television system, a set-top box, anavigation system, a DVD player, a Blu-ray player, a personal computer(PC), a home theater system, and a phone system.

The liquid crystal display according to the aspect of the disclosurefurther includes a power unit, which is not illustrated in the drawings.The power unit generates voltages required to drive the display panelPNL1 and the light valve panel PNL2 using a DC-DC converter. Thevoltages includes a high potential power voltage VDD, a logic powervoltage VCC, a gamma reference voltage, a gate high voltage VGH, a gatelow voltage VGL, a common voltage Vcom, and other voltages. The highpotential power voltage VDD is a maximum value of the data voltage, towhich pixels of the display panel PNL1 will be charged. The logic powervoltage VCC is an IC power voltage of the first and second panel drivingcircuits. The gate high voltage VGH is a high logic voltage of the gatepulse, which is set to be equal to or greater than a threshold voltageof the TFTs of the pixel array. The gate low voltage VGL is a low logicvoltage of the gate pulse, which is set to be less than the thresholdvoltage of the TFTs of the pixel array. The gate high voltage VGH andthe gate low voltage VGL are supplied to the gate driver 30. The gatepulse swings between the gate high voltage VGH and the gate low voltageVGL. The common voltage Vcom is supplied to the common electrode 22 ofthe liquid crystal cells Clc. The power unit divides the high potentialpower voltage VDD and generates the gamma reference voltage. The gammareference voltage is divided by a voltage divider circuit installedinside the first data driver 20 and is divided into positive andnegative gamma compensation voltages depending on a gray scale.

The light valve panel PNL2 precisely controls an amount of lightirradiated onto each pixel in synchronization with data of an inputimage displayed on the pixel array and maximizes a contrast ratio of animage reproduced on the display panel PNL1. The detailed features willbe described with reference to FIG. 3.

Lines are formed on each of the display panel PNL1 and the light valvepanel PNL2. These lines are not transparent and may be formed as metallines having a high reflectance. The metal lines include data lines in avertical direction, gate lines in a horizontal direction, and commonlines in the horizontal direction. The common lines are connected to thecommon electrodes of the pixels and supply the common voltage Vcom tothe common electrodes. Because the metal lines having the highreflectance lead to a reduction in the contrast ratio by reflectingexternal light, the metal lines and the TFTs are covered by a blackmatrix pattern. In this instance, when the lines of the display panelPNL1 overlap the lines of the light valve panel PNL2, the moirephenomenon may be generated in the vertical and horizontal directionsdue to interference of light if a misalignment is generated as shown inFIG. 3. In order to reduce the moire phenomenon, a diffuser sheetdiffusing light may be disposed between the display panel PNL1 and thelight valve panel PNL2. On the other hand, the aspect of the disclosureremoves the horizontal lines from the light valve panel PNL2 and formsthe electrodes of the upper and lower substrates and the lines using atransparent electrode material, thereby minimizing the moire phenomenonwithout adding the diffuser sheet.

When a user watches the liquid crystal display from a front viewingangle, the user may watch an image at a desired luminance. However, whenthe user watches the liquid crystal display from side viewing angles, aluminance and a color of the image may change. As shown in the middlediagram of FIG. 4, the front viewing angle is a viewing angle obtainedwhen the user watches a display surface of the display panel PNL1 at anangle of 90°. The side viewing angle is a viewing angle obtained whenthe user watches the display surface of the display panel PNL1 at anangle leaned to the left side or the right side. In FIG. 4, a leftdiagram is shown at a left viewing angle of 45°, and a right diagram isshown at a right viewing angle of 45°. In particular, because apredetermined gap ΔG is unconditionally formed between the display panelPNL1 and the light valve panel PNL2, a color distortion of the liquidcrystal display including the light valve panel PNL2 may more obviouslyappear from the side viewing angles. In FIG. 4, only blocks of the lightvalve panel PNL2 positioned under pixels represented with white colortransmit light, and other blocks of the light valve panel PNL2 blocklight. In this instance, when the user watches the liquid crystaldisplay from the side viewing angles, luminances of some colors arereduced, and the color distortion appears. A method for adjusting aluminance of the light valve panel PNL2 shown in FIG. 5 may beconsidered, so as to improve the luminance of the side viewing angles.It should be noted that an example illustrated in FIG. 5 is not arelated art.

FIG. 5 illustrates an example of a distorted bright line appearing whena dark block adjacent to a bright block of the light valve panel PNL2 isturned on so as to prevent the color distortion of the side viewingangles. The bright block is disposed under a bright pixel (hereinafter,referred to as “ON-pixel”) of the display panel PNL1 and means a block(hereinafter, referred to as “ON-block”) of the light valve panel PNL2irradiating light onto the ON-pixel. The bright pixel is a pixel towhich data of a high gray level, for example, a white gray level isapplied. The dark block means a block (hereinafter, referred to as“OFF-block”) of the light valve panel PNL2 disposed under a dark pixel(hereinafter, referred to as “OFF-pixel”) adjacent to the ON-pixel ofthe display panel PNL1. The dark pixel is a pixel to which data of a lowgray level, for example, a black gray level lower than the gray level ofthe ON-pixel is applied. As shown in FIG. 5, when luminances of theOFF-blocks adjacent to the ON-block increase, each of red, green, andblue data at the side viewing angles can be seen to have a desiredluminance. Therefore, the color distortion at the side viewing anglescan be reduced or prevented. On the other hand, when luminances of theOFF-blocks increase, luminances of the OFF-pixels may increase. Hence,luminances of the OFF-pixels at the front viewing angle may increase. Inorder to compensate for a reduction in image quality at the frontviewing angle, the luminance of the OFF-pixel may be decreased using amodulation method for reducing a data value of the OFF-pixel adjacent tothe ON-pixel. However, the modulation method may lead to the bright linephenomenon, in which a boundary between the OFF-pixel receiving data andthe OFF-pixel receiving original data looks bright.

The aspect of the disclosure adjusts a luminance of the light valvepanel PNL2 through a gradation method by distributing the voltage to theblock in a manner that a luminance of the OFF-block adjacent to theON-block in the light valve panel PNL2 gradually changes, so as toreduce the luminance and the color distortion at the side viewing anglesand prevent the bright line phenomenon. Further, the aspect of thedisclosure may control a gray level of the OFF-pixel adjacent to theON-pixel in reverse of a gradation luminance control method of theOFF-block.

FIG. 6 illustrates a pixel data modulation method of the display paneland a block luminance control method of the light valve panel. FIG. 7illustrates a luminance of a pixel at a side viewing angle when data anda luminance of the display panel are controlled through a control methodillustrated in (C) of FIG. 6.

In FIG. 6, D1 denotes a location of an ON-pixel and a location of anON-block under the ON-pixel. D2 and D3 respectively denote a location ofan OFF-pixel and a location of an OFF-block under the OFF-pixel.

More specifically, (A) in FIG. 6 illustrates an example where data of ahigh gray level is applied only to an ON-pixel, and only an ON-block isturned on at a high luminance. (B) in FIG. 6 illustrates a method forincreasing a luminance of an OFF-block adjacent to the ON-block by aluminance of the ON-block and reducing a gray level of data to beapplied to an OFF-pixel adjacent to the ON-pixel, so as to improve aside viewing angle.

(C) in FIG. 6 and FIG. 7 illustrate a method for gradually reducing aluminance of an OFF-block as the OFF-block is far away from the ON-blockwhile increasing the luminance of the OFF-block adjacent to the ON-blockby a luminance of the ON-block, so as to improve a side viewing angleand a bright line. Each block of the light valve panel PNL2 is disposedunder pixels of the display panel PNL1 and irradiates light onto thepixels. Thus, there are OFF-pixels in the OFF-block adjacent to theON-block, and gray levels of the OFF-pixels can be individually adjustedas shown in (C) of FIG. 6 and FIG. 7. The pixel data modulation methodmay use the gradation method shown in (C) of FIG. 6. Other methods maybe used. For example, a luminance of the light valve panel PNL2 may usethe gradation method of (C) in FIG. 6, and the pixel data modulationmethod may use the method shown in (B) or (C) of FIG. 6.

FIG. 8 is a cross-sectional view of a light valve panel.

Referring to FIG. 8, the light valve panel PNL 2 includes a second uppersubstrate 200 and a second lower substrate 210.

The second upper substrate 200 includes a first base substrate 201 and asecond electrode 203. The second electrode 203 may be formed of atransparent electrode material such as indium tin oxide (ITO). Thesecond upper substrate 200 may include a black matrix (BM) if necessary.Hereinafter, the second electrode 203 will be referred to as an upperelectrode 203 in this specification.

The second lower substrate 210 includes a second base substrate 211, alight valve data line LVDL, and a first electrode 215. Hereinafter, thefirst electrode 215 will be referred to as a lower electrode 215 in thisspecification.

The lower electrode 215 may be formed of a transparent electrodematerial such as ITO. The lower electrode 215 is disposed over theentire surface of the second lower substrate 201 of the light valvepanel PNL2. The light valve data line LVDL is formed of a transparentelectrode material such as indium tin oxide (ITO) and indium zinc oxide(IZO). The light valve data line LVDL may be formed of a transparentelectrode, so as to prevent the moire phenomenon but is not limitedthereto. The light valve data line LVDL may be formed of a lowresistance metal, so as to compensate for a resistance of thetransparent electrode.

The light valve data lines LVDL are connected to the lower electrode 215through a contact hole CNT to directly supply a light valve datavoltage. Therefore, the light valve panel PNL2 does not need a TFT or agate line (or a scan line). Hence, the aspect of the disclosure canprevent a moire phenomenon and a bright line phenomenon and can furtherreduce the number of manufacturing processes of the light valve panelPNL2 by simplifying a structure of the light valve panel PNL2, therebyincreasing a yield. Further, the aspect of the disclosure omits a gatedriving circuit for driving the light valve panel PNL2 and thus canimplement a lower cost light valve panel PNL2.

A polarizing film 24 (shown in FIG. 2) is attached to the second lowersubstrate 210 of the light valve panel PNL2. A liquid crystal layer 230is formed between the second upper substrate 200 and the second lowersubstrate 210. Alignment layers are respectively formed on the surfacescontacting the liquid crystal layer 230 at the second upper substrate200 and the second lower substrate 210 of the light valve panel PNL2. Aspacer for maintaining a cell gap of the liquid crystal cells may beformed between the second upper substrate 200 and the second lowersubstrate 210 of the light valve panel PNL2.

FIG. 9 is a view illustrating block division of a light valve panelaccording to a first aspect of the disclosure.

Referring to FIGS. 8 and 9, the lower electrode 215 of the light valvepanel PNL2 includes an active area A/A and a bezel area Bezel. There arem×n blocks BL arranged in the active area A/A.

The light valve data lines LVDL are parallel with each other andarranged in a vertical direction (a y-axis direction) in the active areaA/A. Each of the light valve data lines LVDL is connected to blocks BLthrough a contact hole CNT. The light valve data voltage supplied to thelower electrode through the contact hole CNT is distributed to an areaof the block BL. For example, in FIG. 10, when a voltage of 10 V isapplied through a first contact hole CNT1, the voltage close to 10 V isapplied to first to fourth pixels P1, P2, P3 and P4 close to the firstcontact hole CNT1. When a voltage of 0V is applied through a secondcontact hole CNT2, the voltage close to 0V is applied to fifth to eighthpixels P5, P6, P7 and P8 close to the second contact hole CNT2.

The light valve data lines LVDL are arranged vertically in parallel witha column direction (a y-axis direction) of the pixels P. Each of thelight valve data lines LVDL is arranged so as to connect an upper endand a lower end of the light valve panel PNL2 in a straight line. As aresult, the light valve data lines LVDL are arranged evenly over theentire surface of the light valve panel PNL2.

Because the light valve data lines LVDL are evenly distributed over theentire surface of the light valve panel PNL2, it is possible to improvean occurrence of a transmittance difference due to uneven distributionof the light valve data lines LVDL.

The aspect shown in FIG. 9 will be described with reference to acomparative example shown in FIG. 11 as follows.

In the comparative example shown in FIG. 11, contact holes CNT connectedto each of blocks BL disposed in the same column are located on the samevertical axis (y axis). For example, first to fifth contact holes CNT1to CNT5 of a first column connected to first to fifth blocks BL1 to BL5disposed in the first column are arranged on the same vertical axis. Thelight valve data lines LVDL corresponding one-to-one relationship withthe respective contact holes CNT are bent at the right angle in a statein which they are arranged in parallel with each other and are connectedto the respective contact holes CNT. As a result, in the comparativeexample shown in FIG. 11, a density of an area in which the light valvedata lines LVDL are arranged in the light valve panel PNL2 is changed.As shown in FIG. 12, an area A without vertical portions of the lightvalve data lines LVDL has a higher light transmittance than an area Bwhere the vertical portions of the light valve data lines LVDLs aredisposed. That is, in the comparative example, a difference in lighttransmittance occurs between the area A and the other areas depending onwhether or not the light valve data lines LVDL are arranged. If adifference in light transmittance occurs in a planar area of the lightvalve panel PNL2, there is a problem that a luminance difference occursin an image displayed on the display panel PNL1.

On the contrary, in the light valve panel PNL2 shown in FIG. 9, sincethe light valve data lines LVDL are evenly arranged in the planar areaof the light valve panel PNL2, a difference in light transmittance dueto presence or absence of the arrangement of the light valve data linesLVDL can be improved.

FIG. 13 is a view illustrating block division of a light valve panelaccording to another aspect of the disclosure. A sectional structure ofthe light valve panel PNL2 according to the another aspect is the sameas that of FIG. 8.

Referring to FIGS. 8 and 13, the light valve data lines LVDL are formedin an oblique direction with respect to the vertical direction. Thelight valve data lines LVDL each are connected to the blocks BL of thelower electrode 215 through contact holes CNT. The contact holes CNT arearranged at regular intervals along a row direction and at regularintervals along a column direction. The intervals between the contactholes CNT in the row direction and the intervals between the contactholes CNT in the column direction may be different from each other. Aline segment connecting the contact holes CNT arranged in the rowdirection and a line segment connecting the contact holes CNT arrangedin the column direction are orthogonal. As a result, vertical linesegments connecting the contact holes CNT arranged in the columndirection can coincide with boundaries of the pixels P of the displaypanel PNL1 on a plane.

In the light valve panel PNL2 according to the another aspect, the lightvalve data line LVDL is evenly distributed in the active area A/A as inthe first aspect. Accordingly, the light valve panel PNL2 according tothe another aspect can improve a difference in light transmittance dueto presence or absence of the arrangement of the light valve data linesLVDL.

In the light valve panel PNL2 according to the another aspect, since theline segment connecting the contact holes CNT and the boundary line ofthe pixels P in the display panel PNL1 coincide on a plane, it is easyto determine a light valve data voltage.

The light valve data voltage of the light valve panel PNL2 is determinedbased on an image data of the pixels P. In particular, the light valvedata voltage is determined based on the pixels P included in the blockBL unit.

In the aspect shown in FIG. 9, since the blocks BL of the light valvepanel PNL2 are defined in a parallelogram shape, it is not easy todetermine the pixels P included in each block BL. When the light valvedata voltage is determined based on the comparative example in which thevertical line segments connecting the contact holes CNT are straightlines, there is a problem that the image is distorted around the linesegments connecting the contact holes CNT.

On the contrary, in the light valve panel PNL2 of the another aspect,since the blocks BL are formed in a rectangular shape and the boundariesof the blocks BL and the boundaries of the pixels P coincide with eachother, it is easy to determine the light valve data voltage. As aresult, a distortion of the image pattern at the boundary between theblocks BL can be improved.

FIG. 14 is a schematic diagram illustrating a method for determining anangle θ of light valve data lines LVDL. The angle θ of the light valvedata lines LVDL in the present disclosure is defined as an interiorangle formed by the light valve data line LVDL and a vertical axis y ofthe blocks BL.

The light valve data lines LVDL arranged on a side edge of the activearea A/A are arranged obliquely in a bezel area. Therefore, when theangle θ of the light valve data lines LVDL increases, there is adisadvantage that the bezel area increases. In addition, when the angleθ of the light valve data lines LVDL is too narrow, there arises an areawhere an interval between the light valve data lines LVDL is notuniformly arranged.

A horizontal width interval at a point where the light valve data linesLVDL are in contact with upper and lower portions of the active area A/Ais set to correspond to a horizontal width length l1 of one block BL. Asa result, a width of the bezel can be made equal to the horizontal widthlength l1 of the block BL.

The angle θ of the light valve data lines LVDL may be set by thefollowing equation 1.tan θ=L1/(L2×N)  [Equation 1]

In Equation 1, L1 denotes a horizontal width of the block BL, L2 denotesa vertical width of the block BL, and N is the number of rows of theblock BL.

FIGS. 15 to 17 illustrate dummy data lines DDL according to the presentdisclosure.

In the vicinity of the edge of the active area A/A, there may be a dummyarea DA in which the light valve data line LVDL is not disposed. Thedummy area DA is an image display area included in the active area A/Aand is referred to as an area where the light valve data line LVDL isnot disposed. Since a light transmittance is high in the dummy area DA,a difference in luminance may arise between the dummy area DA and thearea where the light valve data line LVDL is disposed.

To improve this, a dummy data line DDL is formed in the dummy area DA asshown in FIGS. 15 to 17.

Referring to FIG. 15, a plurality of dummy data lines DDL have the samewidth as that of light valve data lines LVDL. The dummy data line DDL isnot electrically connected to the lower electrode 215. The dummy dataline DDL allows the light transmittance to be evenly distributed overthe entire surface of the active area A/A.

Alternatively, as shown in FIG. 16, a dummy data line DDL can bedisposed in a large width so as to cover an edge area where a lightvalve data line LVDL is not disposed in the active area A/A.

FIG. 17 illustrates an aspect in which a width of a light valve dataline LVDL is different to cover an edge area of an active area A/A. Thelast light valve data line LVDL shown in FIG. 17 is patterned so as tocover the dummy area in the active area A/A. This dummy line DDL canimprove a difference in transmittance depending on whether the lightvalve data lines LVDL are disposed or not.

Although aspects have been described with reference to a number ofillustrative aspects thereof, it should be understood that numerousother modifications and aspects can be devised by those skilled in theart that will fall within the scope of the principles of thisdisclosure. More particularly, various variations and modifications arepossible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A light valve panel including an active area anda bezel area located outside the active area, comprising: a firstelectrode disposed on an entire surface of a first substrate of thelight valve panel and defined by a plurality of blocks located in theactive area and the bezel area is located where the plurality of blocksis not disposed; a plurality of light valve data lines connected to thefirst electrode through a plurality of contact holes and directlysupplying a light valve data voltage to the first electrode without athin film transistor, a gate line and a scan line in the light valvepanel, wherein each block corresponds to each light valve data line andmore than one pixels, so that the more than one pixels in closeproximity to the plurality of contact holes are supplied with a voltageclose to the light valve data voltage supplied to the first electrode;and a second electrode on a second substrate and facing the firstelectrode, wherein the light valve panel adjusts an amount of light tobe emitted by a difference in voltages supplied to the first and secondelectrodes, wherein the plurality of the light valve data lines extendsin parallel within the active area in an oblique direction with respectto a vertical edge along a Y-axis direction of the active area and formsan angle (θ) with respect to a vertical edge along the Y-axis directionof each block in the active area, and four corners of each block aredefined by four vertically (the Y-axis direction) and horizontally (anX-axis direction) adjacent contact holes of the plurality of contactholes, and wherein the angle (θ) between the plurality of light valvedata lines and the vertical edge along the Y-axis direction of eachblock in the active area is determined by an equation of tanθ=L1/(L2×N), where L1 is a length of a horizontal edge of each block, L2is a length of the vertical edge of each block and N is a number of rowsof the blocks in the active area.
 2. The light valve panel of claim 1,wherein the bezel area has a width substantially the same as ahorizontal width of the plurality of blocks.
 3. The light valve panel ofclaim 2, wherein a tangent of an angle is the horizontal width of theplurality of blocks divided by a vertical width of the active area. 4.The light valve panel of claim 1, wherein the plurality of contact holesis disposed in parallel with a vertical edge of the plurality of blocks.5. The light valve panel of claim 1, further comprising a dummy linedisposed at a dummy area where the light valve data line is not disposedat the active area.
 6. A liquid crystal display device comprising: adisplay panel including a plurality of pixels to which an input image isapplied; a backlight unit irradiating light onto the display panel; anda light valve panel disposed between the display panel and the backlightunit, the light valve panel configured to adjust an amount of theirradiated light from the backlight unit depending on the input image,wherein the light valve panel where an active area and a bezel arealocated outside the active area are defined, the light valve panelincludes: a liquid crystal layer; a first electrode disposed on anentire surface of a first substrate of the light valve panel and definedby a plurality of blocks located in the active area and the bezel areais located where the plurality of blocks is not disposed; a plurality oflight valve data lines connected to the first electrode through aplurality of contact holes and directly supplying a light valve datavoltage to the first electrode without a thin film transistor, a gateline and a scan line in the light valve panel, wherein each blockcorresponds to each light valve data line and more than one pixels, sothat the more than one pixels in close proximity to the plurality ofcontact holes are supplied with a voltage close to the light valve datavoltage supplied to the first electrode; and a second electrode on asecond substrate and facing the first electrode with the liquid crystallayer interposed therebetween, wherein the light valve panel adjusts anamount of light to be emitted by a difference in voltages supplied tothe first and second electrodes, wherein the plurality of the lightvalve data lines extends in parallel within the active area in anoblique direction with respect to a vertical edge along a Y-axisdirection of the active area and forms an angle (θ) with respect to avertical edge along the Y-axis direction of each block in the activearea, and four corners of each block are defined by four vertically (theY-axis direction) and horizontally (an X-axis direction) adjacentcontact holes of the plurality of contact holes, and wherein the angle(θ) between the plurality of light valve data lines and the verticaledge along the Y-axis direction of each block in the active area isdetermined by an equation of tan θ=L1/(L2×N), where L1 is a length of ahorizontal edge of each block, L2 is a length of the vertical edge ofeach block and N is a number of rows of the blocks in the active area.7. The liquid crystal display device of claim 6, wherein the bezel areahas a width substantially equal to a horizontal width of the pluralityof blocks.
 8. The liquid crystal display device of claim 7 wherein atangent of an angle is the horizontal width of the plurality of blocksdivided by a vertical width of the active area.
 9. The liquid crystaldisplay device of claim 6, the plurality of contact holes is disposed inparallel with a vertical edge of the plurality of blocks.
 10. The liquidcrystal display device of claim 6, further comprising a dummy linedisposed at a dummy area where the plurality of light valve datalines—is not disposed at the active area.
 11. A light valve panel havingfirst and second substrates configured to adjust an amount of light froma light source in accordance with an input image to be displayed, andincluding an active area and a bezel area located outside the activearea are defined, the light valve panel comprising: a first electrodedisposed on an entire surface of the first substrate and defined by aplurality of blocks located in the active area and the bezel area islocated where the plurality of blocks is not disposed; a plurality oflight valve data lines connected to the first electrode through aplurality of contact holes and directly supplying a light valve datavoltage to the first electrode without a thin film transistor, a gateline and a scan line in the light valve panel, wherein each blockcorresponds to each light valve data line and more than one pixels, sothat the more than one pixels in close proximity to the plurality ofcontact holes are supplied with a voltage close to the light valve datavoltage supplied to the first electrode; a second electrode on thesecond substrate and facing the first electrode; and liquid crystalmolecules between the first and second substrates, wherein the liquidcrystal molecules are synchronized with the input image to be displayedby the light valve voltage, wherein the light valve panel adjusts anamount of light to be emitted by a difference in voltages supplied tothe first and second electrodes, wherein the plurality of the lightvalve data lines extends in parallel within the active area in anoblique direction with respect to a vertical edge along a Y-axisdirection of the active area and forms an angle (θ) with respect to avertical edge along the Y-axis direction of each block in the activearea, and four corners of each block are defined by four vertically (theY-axis direction) and horizontally (an X-axis direction) adjacentcontact holes of the plurality of contact holes, and wherein the angle(θ) between the plurality of light valve data lines and the verticaledge along the Y-axis direction of each block in the active area isdetermined by an equation of tan θ=L1/(L2×N), where L1 is a length of ahorizontal edge of each block, L2 is a length of the vertical edge ofeach block and N is a number of rows of the blocks in the active area.12. The light valve panel of claim 11, wherein the vertical edge of eachblock and each light valve data line forms the angle (θ) between 0° and90°.
 13. The light valve panel of claim 11, further comprising a dummyline disposed at a dummy area where the plurality of light valve datalines—is not disposed, wherein the dummy line is electrically insulatedfrom the first electrode.
 14. The light valve panel of claim 11, whereinthe plurality of contact holes is disposed in parallel with the verticaledge of each block.
 15. The light valve panel of claim 11, wherein atangent of an angle is a horizontal width of the plurality of blocksdivided by a vertical width of the light valve panel.